I don't know if there is or anything about disk encryption for windows.
If grub is installed, grub should load instead of windows bootloader forcing you to decrypt before your boot selection. This will give the appearance that windows is encrypted by luks.
Army of Darkness.
Rice is great when your not very hungry but you want a thousand of something. ~ Stephen Wright
Sorry, that's all I got. Best of luck!
Di you have an Optimus computer with 2 GPUs? Is your computer using a nvidia card? If so you might look into prime -> arch wiki.
You may or may not have to start D-resolve in a terminal prime-run %command% to force prime render offload.
This is awesome! I can't wait to check it out.
Also congratulations on being approached by and joining KDE's ecosystem.
Does Dad know?
My explanation above just gives the illusion of entire computer encryption.
Say you have a separate hd for each OS. Each with bootloaders on their drives. To bypass grub running luksopen you can boot directly into windows in the bios, in this instance the windows bootloader will be used to load windows. However if your bios is set to boot your Linux HD and grub has successfully found your windows drive and created a boot entry for it, it should be selectable after luks decryption. This can give the illusion that windows is encrypted while not really being so to an advanced user. There is nothing preventing you from mounting windows as its not really encrypted, just the way grub loads Luks before OS selecton. If I remember correctly systemd-boot loads OS selection before luksopen giving no appearance of encryption till after your OS selection, you should be able to boot windows without the false sense of drive decryption.